Income Taxes (Narrative) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Income Taxes [Line Items]
Benefit from the tax incentives	$ 4.3	$ 0.7
Benefit from the tax incentives, per share	$ 0.13	$ 0.02
Possible additional tax payments	12
Balance of unrecognized state tax positions	0.1
State And Foreign Net Operating Loss Carryforwards [Member]
Income Taxes [Line Items]
Valuation allowance	1.3	1.3
Excess Capital Losses From Investments And Other Related Items [Member]
Income Taxes [Line Items]
Valuation allowance	15.5	9.3
Asset Impairments In Foreign Jurisdictions [Member]
Income Taxes [Line Items]
Valuation allowance	$ 1.9	$ 1.8
Terphane Ltda [Member]
Income Taxes [Line Items]
Current effective tax rate	15.25%
Income tax rate	6.25%
Percentage of social contribution on income included in current effective tax rate	9.00%
Brazilian [Member]
Income Taxes [Line Items]
Federal statutory income tax rate	34.00%
Income tax rate	25.00%
Percentage of social contribution on income included in federal statutory income tax rate	9.00%

Current Effective Tax Rate Including Social Contribution On Income

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Current Effective Tax Rate Reconciliation Social Contribution On Income

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- Definition

Effective Income Tax Rate Reconciliation Federal Statutory Tax Rate Excluding Social Contribution On Income

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Effective Income Tax Rate Reconciliation Federal Statutory Tax Rate Including Social Contribution On Income

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Effective income tax rate reconciliation social contribution on income.

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- Definition

Unrecognized state positions expected to reverse from statute of limitations lapse next twelve months.

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- Definition

The estimated range of reasonably possible losses resulting from an adverse position taken by a taxing authority.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 14

-Paragraph 3

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (d)(3)

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The amount of income taxes from which a reporting entity is exempt or for which it will receive a reduction in income taxes as a result of the income tax holiday granted by the taxing jurisdiction.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 11.C)

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 11

-Section C

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Per share amount effect of the income tax benefit resulting from the income tax holidays granted by taxing jurisdictions.

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- Definition

The amount of the valuation allowance recorded as of the balance sheet date pertaining to the specified deferred tax asset for which an assessment was made that it is more likely than not that all or a portion of such deferred tax asset will not be realized through related deductions on future tax returns.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 43

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Valuation Allowance

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